Fractionating system



Feb. 25, 930. 1

2 Sheets-Sheet 1 ATTORNEY.

M. B. COOKE FaAcT-Iormme sYsTau Original Filed July 24, 1925 2 Sheets-Sheet 2 7 Y INQENTOR. 4 iii/"a5 C I? ATTORNEY.

Patented Feb. 1930 I UNITED STATES EPATENIT OFFICE vIIIILAIU'IRIIGE B. GQOKE, OF PLAINI IELD, NEW JERSEY, ASS IGNOR TO THE ATLANTIC RE- FINING COMPANY, OF, PHILADELPHIA, PENN SYLVANIA, A CORPORATION OF PENN- SYLVANIA FRACTIONATING SYSTEM Application filed July 24,1925, Serial No. 45,796. -Renewed. February 20, 1929.

This invention relates to improvements in fractionating towers and refers more particularly to a tower of thebubble type and the treating of vapors such as oil vapors, acid vapors, or any type of vaporous material in which a close fractionation or restricted range of boiling-points is desired. I

One aspect of novelty of the invention lies ina combination type of bubble tower which is equipped not only with the bubble pools through which the vapors are caused to percolate, but also with a series of packed zones, which zones contain an inert or catalytic material which serves as anobstruction to the vapors,'and separate out any mechanically entrained liquid material carried along with the vapors and supported in the form of a mist or minute liquid particles. However, .it is to be understood that the invention is notlimited to said combination type tower.

' My invention resides in apparatus of the character hereinafter described and claimed. ,As specific examples of some of the forms my apparatus may take, reference is had to i the accompanying drawing, in which:

Fig. 1 is a sectional side type of tower.

Fig. 2..is a plan view taken on line 22 Y of Fig.il,.in the direction indicated by the 1 the caps.

arrows," with parts broken away to disclose the details of the bubble caps.

Fig. 3 is'a side elevational view of one of Fig. 4'is a sectional view taken through the bubble cap shown in Fig. 3.

.Fig; 5 is a view of an inverted cap "as in Fig. 3, showing the. shape of the hood or upper plate.

- Fig. 6 shows a tower a slightly modified type-0f n truction.

Referring to the drawings, at l is shown the usual type 0t 'fractionatin tower which is preferably cylindrical in orm. Vapors are introduced .into the tower through a vapor inlet line 2 at the bottom of the tower and discharged at an upper vapor outlet designated as 3. Withinthe tower are positioned a plurality of trays 4 equipped with risers 4 which conduct the vapors introduced at the bottom of the tower upwardly. Sur- The vapors passing through the toothed or serrated edges of the caps, percolate through the several pools of liquid supported upon the trays, the depth of each pool being determined by the. height-of the downcomer or overflow standpipes 7 above the bottom of the respective tray? With the accumulation of condensate in the pools, the excess material overflows through the top of the standpipes to the next succeeding pool below. This the reflux material is gravitated downwardly against the passage of the rising vapors.

The tops of the caps are shaped to form a flat surface or grid designated as 8 in the drawings. The tops of the caps shown are hexagonal in form in order that they fit toview-of a preferred gether to forma continuous flat surface or grid upon which is placed the packing material diagrammatically shown at 9. The topsare perforated by holes 10 which serve to permit a free passage of the vapors which rise about the serrated edges of the caps and pass upwardly through the fiat top grid and packing material carried thereupon.

In place of the caps described and shown in Fig. 1, the usual type of bubbler cap 5 may be used as shown in Fig. 6. These bubbler caps serve the purpose of reversing the flow of the vapors and causing the same to percolate through thepools of li uidsupported upon the separate trays in t e tower.. Between the trays is positioned'an annular ring'll carried by the angle support 12. To thi'sfannular ring is bolted a circular perforated grid 12'. This grid supports the packing material 9 in a manner similar to the supporting grid formed by the fitted tops 8 of the caps 5 shown in Figs. 3 and 4. It is under- .stoodthat, if so desired, a grid such as that shown at 12 will be interposed below each of the bubble tower pools throughout the length .of the towers such as that partially shown in Fig. 6. Otherwise, the construition of the tower is identical in form to the trays by means of risers 4 surmounted by bubble caps j.

From the separate pools, if so desired, liquid condensates or fractions may be drawn off through the lines 13, the heaviest material passing ofl from the fluid delivery line 14. In actual operation, a bubble tower fractionator is fecognized as one of the most eflicient type of mechanism, as a relatively close fractionation is attained and a most complete and intimate contact of the condensate and vapors makes for a uniform final product as well as fractions of restricted boiling point range. It is, however, appreciated that there is a certain amount of mist or liquid carried along or entrained in the vapors as they percolatc through the liquid pools. The bursting of the bubbles, caused by the vapors during their percolation through the pools, releases a considerable quantity of liquid mist which is readily taken up and carried along with the vapors. This entrained material is difficult of j separation due to its light weight and a supporting movement or energy set up by the velocity of the vapors which readily carries this material along through the successive poolsand overhead to the final condensing zone where it adds undesirable constituents to the final product. By interposing between the pools a vapor arrester of'this character or a similar type which has the deentraining effect upon the vapors, and particularly effects removal of entrained liquid from the vapors to cause the same to v be separated out and trapped back to the pool below, a much closer fractionation is eflected and a more desirable final product produced as wellas the intermediate fractions which may be drawn oif from the individual pools. A zone built up of packing materialsuch as inert ceramic substance or a catalytic material is shown as a possible type of vapor arrester although it is understood that any equivalent means which will effectively arrest this entrained mist to cause the same to separate out from the vapors into contact with the vapors from'which the. '60

and be returned to the pool below, is contemplated by the present invention.

A A feature of particular importance is that the reflux liquid in passing downwardly through the column is not permitted to come entrained liquid has beenremovedl This is of'particular importance in that if the reflux liquid were permitted to come into contact with-the disentrained vapors, reentrainment would take place and permit the vapors to pass to the next plate.- above carrying with them substantial quantities of entrained liquid.

It shall be understood that my invention is not limited to specific details of structure, and that in invention comprehends the utilization 0 equivalent structures.

It shall further be understood that my invention is not limited to anyparti cular type means intermediate the trays for-separating out entrained liquid and drying rising vapor; diametrically opposite overflow pipes for conducting reflux liquid from a higher tray to a lower tray out of contact both with said means and with the rising vapors.

2. A fractionating tower of the bubble I .type, comprising a shell having a lower va-- por inlet and an upper vapor outlet, a' plu rality of liquid supporting trays positioned one above the other, capped risers forming vapor communication between the trays, drying means intermediate the trays for removing entrained liquid from the vapors, diametrically opposite overflow pipes for gravitate ing the reflux liquid both out of contact withsaid drying means and with the rising vapors.

3. .A. fractionating tower of the bubble ty e comprising a shell having a lower vapor inet and an upper vapor outlet, a plurality of liquid supporting trays positioned "one above the other, capped risers forming-vapor communication between the trays, drying means comprising packed material intermediate the trays for removing entrained liquid from the vapors, diametrically opposite overflow pipes for gravitating the'liquid'downwardly from tray to tray out of contact with\ said drying means.

4. A fractionating tower of the bubble type comprising a plurality of liquid supporting trays positioned one above the other, iisers 'on each tray, forming vapor communication between ad acentitrays, perforated caps sur-- mounting said risers and'forming a continuous foraminous grid between adjacent trays adapted to support inert ceramic material.

5 A ,fractionating tower having a lower vapor inlet and an upper vapor outlet, a plurality of liquid supporting trays positioned one above the other, vapor risers for permitting vapors to pass through said trays, means trays positioned one above the other, avapor aa b oth w ith said-means and with the rising rality of liquid supporting trays positioned one above the other, vapor risers for permitting vapor to pass through the trays, drying means comprising inert packingmaterial intermediate the trays for removing entrained liquid from the vapors, and overflow pipes for conducting the reflux liquid downwardly from tray to tray out of contact with said drying means. 7. A fractionating tower comprising a plu rality of liquidsupporting trays positioned one above the other, vapor risers for each tray, perforated caps surmounting'said risers and forming a contin'uous-foraminous grid between adjacent trays adapted to support inert ceramic material.

8..A fractionating apparatus comprising a column, a plurality of liquid supporting riser through at least one of said trays, means below at least said one of said trays for separating out entrained liquid and drying rising vapors, means for conducting liquid from said one of said trays to 'a point below said separating means without permitting the liquid to come into contact with the separating means. r

9. In fractionating apparatus, the combination with a bubbler plate having vapor uptakes, of bubbler caps, each of said bubbler 1 caps comprising'a member adapted to extend. -over the associated vapor uptake, and a top' on said-member having per orations for the passage of vapors therethrough, the tops of said bubbler caps registering with each other to form a substantially continuous grid.

10. A bubbler cap comprising a member I ada ted to extend over avapor uptake in'a aboveat least one of said trays for separating entrained liquid and drying rising vapors,

and overflow pipes for conducting liquid from higher trays to lower trays.

13. In combination, a fractionating column, a bubbler plate having a downflow pipe and a plurality of fluid uptakes, caps covering said fluid uptakes, and structure above said caps providing numerous restricted fluid passages for separating entrained liquid from and drying rising fluid.

14. In combination, a fractionating column, a bubbler plate having at least one fluid uptake, means above said bubbler-plate for separating entrained liquid from and drying rising fluid, and means for passing liquid so separated to a point below said bubbler plate while preventing contact thereof with rising 15. In combination, a bubbler plate having at least one fluid uptake, means above said plate for separating entrained liquid from p the fluid, and means for assing liquid from a point above to a point elow said separating means and out of contact therewith.

16. Fractionating apparatus comprising a column having a vapor inlet adjacent its lower end and a vaporoutlet adjacent its upper end,

B; cooKa' bub ler plate, a top on-said member forming a flat surface, said top having sides registering with the-sides of the tops of similar cap. members when placed adjacent each other on a bubbler plate, said top having perforations adapted for the passage of vaporstherethrough.

11. A bubbler cap comprising a member adapted to extend over a vapor uptake in a bubbler plate, said member having a top forming a flat surfaceand extending laterally beyond said member, said top having such geometrical shape that the sides thereof fitg; snugly with sides of tops of similar-caps when placed adjacent each other upon a bubbler plate, fins supporting said top upon said memher, and said top having perforations adapted .for the passage of vapo 12. A fractionating tower having a lower vapor inlet and an upper vapor outlet, :1 plurality of liquid supporting trays positioned one above the other, vapor users for permitting vapors to pass through saidtrays, means 

